Field of the Invention
The present invention relates to a high frequency circuit module in which high frequency circuits are mounted on a multilayer circuit substrate, and particularly relates to a mounting structure of a high frequency switch and filters.
Description of Related Art
Conventionally, switching circuits utilizing PIN diodes have been employed in circuit modules including high frequency switches used for mobile phones. However, with a recent trend of handling multiple bands and higher communication frequency bands, high frequency switches utilizing FET switches have been more widely used. Known examples of circuit modules with these types of high frequency switches include the circuit modules disclosed in Patent Documents 1 to 3. A high frequency switching module in which a high frequency switch IC and surface acoustic wave (SAW) filter are mounted on the surface of a multilayer circuit substrate is disclosed in Patent Documents 1 and 2. A high frequency module in which a high frequency switch is embedded in a multilayer circuit substrate is disclosed in Patent Document 3.